Seal for centrifugal molds



July 7, 1942. 8 s.- L. CONNER ETAL SEAL FOR CENTRIFUGAL MOLDS Filed July19, 1941 EtevEnLJZcmner MiChaE1E.YatsEvitch Wi1l'1amA.Ba1\/Er-t @MJPatented July 7, 1942 UNITED STATE PATENT OFFICE SEAL FOR CENTRIFUGALMOIlDS Steven L. Conner, United States Army, Watervliet,

N. Y., Michael G. Yatsevitch, Cornish, N. H., and William A. Calvert,Brighton, Mass.

Application July 19,1941, Serial No. 403,118

'7' Claims. (CI. 22-65) .(Granted under the act of March 3, 1883, as

amended April 30, 1928; .370 0. G. 757) It is customary to provide intubular chill sists in the construction, arrangement and combination ofelements described hereinafter and pointed out in the claims forming apart of this I specification.

A practical embodiment of the invention is illustrated in theaccompanying drawing wherein: I

Figure 1 :is an elevatlonal view, in section, of

- the venting end of a centrifugal chill mold with plug and seal. v

Figures 2 to 6 are similar views showing modifications of the plug andseal.

Referring to the drawing by characters of reference there is shown inFigure 1 a tapered chill mold I and nested stopper 2 having an axialbore 3. The seal and protector unit is composed of, a plate 4, cup 5,gagger irons 8 and refractory filling l. The bore 3 of the stopper 2 iscontinued through the seal unit, including the refractory. The cup 5 hasa slight clearance from the walls of the mold l and on-heating willexpand into sealing engagement therewith. The use of refractory materialtendsto preserve the entire stopper assembly and maintain .aconstantsize vent hole. Likewise, the use of materials of low thermal.conductivity produces a beneficial effect on the resulting structure ofthe solidified casting.

While the drawing shows a seal unit at the vent end of a mold, it willbe understood that similar units may be employed at the pouring end forsimilar purposes.

In Figure 2 is shown a simple but highly suc-' cessful type of sealwherein a disk of preformed refractory 8 is flxed'to a stopper 9 bymeans of refractory.

In Figured is shown a stopper [5 having an axial bore l6 terminatingwithin the stopper. Oblique branch bores I! and a transverse bore l8help to carry off the gases by centrifugal action. In addition thetransversebore l8 may be utilized to receive a pin or other device forhandling. An annular channel IS in the inner face of the stopper isfilled with refractory which serves to hinder chilling of the moltenmetal which might otherwise foul the bore Hi.

In the stopper of Figure 5 a sealing cup 10 is rznl'ovided to cover anannular refractory insert In Figure 6 is shown a stopper .22 ofconventional design with a sealing member composed of two sealing cups23 welded together and holding between them a body of refractorymaterial 24. The latter inhibits chilling of splashed metal, and thesmall passage 25' in the sealing unit limits the amount of errant metalgaining the vent passage in the stopper.

We claim:

1. A self-sealing stopper for the open end of the bore of a centrifugalchill mold comprising a main body portion having an axial vent passage,and an axially perforated mold-sealing portion fixed to a face of thebody portion for resisting the longitudinal thrust of the molten metalthereagainst, said sealing portion comprising a heat expanding metalliccup member conforming to the wall of the mold and lined with arefractory, and anchor meansin the cup portion for holding therefractory in place.

2. A self-clamping stopper for the open end of the tapered bore of acentrifugal chill mold comprising a frusto-conical main body portionadapted to be seated in the small end of the bore and having an axialvent passage, a facing of refractory on one endof said stopper and sizedto span the mold, and means holding said facing to said stopper.

3. A self-sealing stopper for the open end of the bore of a centrifugalchill mold comprising a main body portion having an axial vent passage,a mold sealing heat expandingmetallic cup disposed with its base on aface of said stopperfor resisting the longitudinal thrust of the' moltenmetal, removable means holding said cup to said stopper, refractorymaterial in said 'cup, and through openings in said cup and saidrefractory aligned with the vent passage in the stopper.

4. In a self-sealing stopper for a centrifugal chill mold having anaxial bore open at one end,

a faced portion on said stopper, an annular channel in said facedportion concentric with said bore, said channel adapted to promotecircumferential expansion of the stopper from the thermal influence ofthe molten metal on the stopper whereby radial pressure is exerted onthe mold, and refractory material in said channel.

5. A stopper as in claim 4 in combination with a centrally perforatedcup-shaped member seated on said faced portion and of a size to seal thechill mold when heated.

6. A self-sealing stopper for the open end of the bore of a centrifugalchill mold comprising a main body portion having an axial bore for-venting and a faced portion normal to the bore,

a heat-expanding mold sealing member on said faced portion conforming tothe wall of the mold comprising cup-shaped metallic elements joined attheir rim portions, refractory material in the space confined by saidelements and a through opening in said sealing member coaxial with saidbore.

7. Av self-sealing stopper for the pouring end of the bore of acentrifugal chill mold comprising, a main body portion having an axialvent passage, a mold sealing heat expanding metallic cup disposed withits base on a face of the stopper for resisting the longitudinal thrustof the molten metal, refractory material in the cup, and throughorifices of reduced diameter in the cup and refractory aligned with thevent passage for shaping the fluid stream being poured therethrough.

' STEVEN L. CONNER.

MICHAEL G. YATSEVITCH. WILLIAM A. CALVERT.

